I have absolutely no knowledge of ABS plastic vs Fiberglass for durability, but one of the main best option for cost trunk I've been able to find near the same capacity is the Mutazu DMY (cracks me up how a couple shops I've looked at have the DMY listed under "their" model number and list it for $300) and with complaints I've heard about the quality not being consistant (some "sometimes" issues corners rattle, locks not straight or sturdy, durability of the ABS etc.. etc..) I thought I'd check into this one.

Any thoughts? Any experience with the product? Looking to get me some education here, and I thank you for any provided.

I thank you for the info on the product. You listed the two main things I'm after. Quality American made and a good reputation for the builder. I'm wanting a trunk I can bolt to the bike and leave it there permanently (I'm in IT, the bike is my main transportation instead of my car and I already have a several 1 - 2 week long trips planned for next summer)

After searching reviews on the Mutazu, I am leery of how long one of those would last on my bike with daily use. If it needs some prepwork for permanent use / good looks, I can live with that

Only downside is that the "required STD full wrap around harley back rest" is another $225 but then again, I may not be needing that.

I considered buying one of these Cruiser Cases, which are American made: Leather Lyke

I had LeatherLyke saddlebags on my Vulcan, and was very happy with their sturdiness, so I was pretty confident that a trunk made by them would be good quality ... but the look just wasn't right on my Victory.

I take that as it will need to be painted, just a cost that has to be considered.

3/16 fiberglass is going to be PLENTY sturdy.

As for you original question, late modle HD hard bags are abs plastic, they are strong, sturdy and probably flex alittle more than fiberglass. That's not all bad, alittle flex is better than too rigid that cracks rather than flexes.

I have Mutazu trunk installed for a year, and I also use the bike instead of car every day. The trunk is usually full of bulky and heavy stuff. No complains at all! It survived all kinds of bad weather, heavy loads, serving as a back support for a pillion and even a bang in the accident.
I am totally happy with Mutazu.